In the past few years since the cloning of the gene defective in cystic fibrosis, much has been learned on the function of the protein cystic fibrosis transmembrane conductance regulator (CFTR) and on the mechanisms regulating its expression. Based on the current understanding of the processes involved in lung disease progression, a number of approaches have been developed using not only gene therapy, but also pharmacological agents. Several of these agents have been reported to restore function to CFTR with specific mutations.